Sadly, I didn't get around to bench testing the grill block this weekend. I ran into a snag. I was hoping to use a plastic flexible pushrod to actuate the grill block. These are the kind used on radio control airplanes and they look like the image below.
The problem is, that my bend radius is around 1" which is really tight. The plastic pushrod doesn't like to bend that tight. The outer tube ends up pinching the plastic rod inside and the door lock actuator won't have enough power to push it.
So, I'm now trying to think of other simple & cheap ideas here. If anyone is aware of a more flexible pushrod I'd love to hear about it. Otherwise I think I'm going to be stuck adding a 90 degree pivot arm to the assembly. It won't be expensive, but it will just add more complexity to the whole thing.
Doh, just had an idea while writing this. If I sanded down the inner rod it would have more clearance and would probably work just fine. I'll give that a try and see how it works out. Still open to other ideas though.